An immunity analyzer is usually used to detect a number of target components in blood, urine, or the other body fluid in clinical laboratories. The immunity analyzer needs to support a number of immunity reaction modes, such as a competition method, a sandwich method, an indirect method, a capture method, etc. The immunity analysis usually includes a radioimmunoassay (RIA), an euzymelinked immunosorbent assay (ELISA), and a luminescence immunoassay (LIA). The luminescence immunoassay has become a major technology used in a clinical immunoassay analyses due to advantages of environmental protecting, a high detecting sensitivity, and a wide detecting range. The luminescence immunoassay is a new label-type immunoassay technology for detecting a trace antigen or antibody by combing a luminescence analysis with an immunoreaction, which combines the high sensitivity of chemiluminescence and the high specificity of immunoreaction. Take one-step sandwich method as an example, the main principle of the luminescence immunoassay is described as below: in order to test a target component in a sample, antibodies/antigens corresponding to the target component can be coated on a number of magnetic beads to form a magnetic bead reagent, and the antibodies can be labeled by a specified marker to form a labeling reagent. Generally, several kinds of reagents are needed in one analysis item, such as the magnetic bead reagent, the labeling reagent mentioned here, etc. The different kinds of reagents of a same analysis item can be received in a number of different reagent containers or in a number of different cavities of a same reagent container. During a test process, the sample containing the target component is first mixed successively with the magnetic bead reagent, the labeling reagent, and other reagents to form a reaction solution of the sample and the reagents, which is incubated under certain conditions to form a reaction complex. Then, unbound markers, reagents, and components of the sample in the reaction system are removed by using bound-free (B/F) separation technology. Afterwards, a signal reagent is added into the reaction solution, with which the marker of the reaction complex reacts (or catalyzes the signal reagent) and then illuminates. There can be one or more kinds of signal reagents, such as luminescent substrate solutions, trigger solutions, pre-trigger solutions, enhanced luminescence substrate solutions, etc. Also, there are numerous methods to realize the bound-free separation technology. In addition to the above-mentioned magnetic bead method, other methods of coating antibodies on a wall of a reaction container or on plastic beads can also be used.
Considering that immunoreaction modes for different target components have different features, a luminescence immunity analyzer usually employs the following conventional test modes:
(1) One-Step Test Mode
FIG. 1 illustrates a one-step and one-separation test mode, which is the simplest test mode, in which a reagent is added only once during the test process. A sample and a reagent are added into a reaction container and mixed together to form a reaction solution. Thereafter, the reaction container containing the mixed reaction solution is placed under a thermostatic condition to perform an incubation reaction for a certain period of time. After the incubation reaction, a bound-free separation is performed on the reaction solution. A signal reagent is added to the reaction solution after the bound-free separation, and then the reaction container containing the signal reagent is placed under a thermostatic condition to perform an incubation reaction for a certain period of time, after which an optical detection of the reaction container is performed. FIG. 2 illustrates another test mode, in which the optical detection of the reaction container is performed without incubation after the signal reagent is added. An example includes a chemiluminescence test mode, which is based on electrochemical luminescence or flash system.
(2) Two-Step and One-Separation Test Mode
Referring to FIG. 3, a sample and a reagent (named a first reagent, which may include several kinds of compositions) are added into a reaction container and mixed together to form a reaction solution. Thereafter, the reaction container containing the mixed reaction solution is placed under a thermostatic condition to perform an incubation reaction for a certain period of time (named a first incubation). Then, a reagent (named a second reagent, which may include several kinds of compositions) is added into the reaction container and mixed with the reaction solution. Thereafter, the reaction container containing the mixed reaction solution is placed under a thermostatic condition to perform an incubation reaction for a certain period of time (named a second incubation). After the second incubation, a bound-free separation is performed to the reaction solution. A signal reagent is added to the reaction solution after the bound-free separation, and then the reaction container containing the signal reagent is placed under a thermostatic condition to perform an incubation reaction for a certain period of time, after which an optical detection is performed. As mentioned above, in some tests, the optical detection is performed directly without incubation after the signal reagent is added.
(3) Two-Step and Two-Separation Test Mode
Referring to FIG. 4, a sample and a reagent (named a first reagent, which may include several kinds of compositions) are added into a reaction container and mixed together to form a reaction solution. Thereafter, the reaction container containing the mixed reaction solution is placed under a thermostatic condition to perform an incubation reaction for a certain period of time (named a first incubation). After the first incubation, a bound-free separation is performed to the reaction solution. Then, a reagent (named a second reagent, which may include several kinds of compositions) is added into the reaction container and mixed with the reaction solution. Thereafter, the reaction container containing the mixed reaction solution is placed under a thermostatic condition to perform an incubation reaction for a certain period of time (named a second incubation). After the second incubation, a bound-free separation is performed to the reaction solution. A signal reagent is added to the reaction solution after the bound-free separation, and then the reaction container containing the signal reagent is placed under a thermostatic condition to perform an incubation reaction for a certain period of time, after which an optical detection is performed. As mentioned above, in some tests, the optical detection is performed directly without incubation after the signal reagent is added.
In addition to the conventional test steps mentioned above, there are also some special test steps, such as a sample pre-treatment step, a sample pre-dilution step, and three-step test mode, etc.
The existing luminescence immunity analyzers can be classified as single-mode analyzers and multi-modes analyzers according to the flexibility of the incubation time duration and test steps. In a single-mode luminescence immunity analyzer, reaction containers are transported to different executing stations via a “fixed” rotation of an incubation unit. The fixed rotation means that a rotation distance or a step increment of the incubation unit in each periodic time period (cycle) is invariable and does not change with the incubation time duration, such that the incubation unit drives reaction containers thereon to move regularly. Thus, these kinds of immunity analyzers only support a fixed combination of several test steps and several kinds of invariable incubation time durations, for example, only the one-step and one-separation test mode or two-step and two-separation test mode can be realized, the incubation time duration of which can be several fixed time periods or an integral multiple of a fixed time period, such as 15 minutes, 30 minutes, or 45 minutes etc. In this regard, the incubation unit can transport the reaction containers thereon in a fixed step increment several times to realize the incubation time duration and after the incubation to reach an executing station capable of performing a specific operation by designing a transport logic. The multi-mode luminescence immunity analyzers can support flexible combinations of several test steps and variable incubation time durations. Namely, the conventional test steps and the special test steps mentioned above can be combined flexibly, and the incubation time duration can be set flexibly, from several seconds to a few minutes, such as 15 seconds, 6 minutes, 10.5 minutes, 60 minutes, etc. The single-mode luminescence immunity analyzer is lack of flexibility, and the analysis mode of the single-mode luminescence immunity analyzer is limited. The incubation time duration of the single-mode luminescence immunity analyzer cannot be adjusted according to the requirements of different test items, which degrades the analysis performance or the test flux of some test items. The multi-mode luminescence immunity analyzers can choose optimized test steps and incubation time duration according to the features of test items, which makes the analysis performance ideal.
In practice, the incubation time duration depends on the test items. It is ideal to make the incubation time duration adjustable according to the type of test items. In the multi-mode luminescence immunity analyzer, reaction containers are transported to different executing stations via a “self-adaptive” rotation of the incubation unit. The self-adaptive rotation means that the rotation distance of the incubation unit in each periodic time period can be adjusted according to the test steps and the incubation time duration of each test item, namely, the rotation distance of a self-adaptive rotation of the incubation unit, can be varied with the requirements of the test steps and the incubation time duration. The executing stations include, but are not limited to, a sample injecting station, a reagent injecting station, a move-in station of moving a reaction container in, a move-out station of moving a reaction container out, and a detecting station. At least one operation mechanism for performing a specific operation on a reaction container is arranged around every executing station, such as injecting apparatuses for injecting a sample and injecting a reagent (e.g. a sample needle and a reagent needle), a delivering mechanism for delivering a reaction container (e.g. a gripper), a detection device for detecting a signal of the analyte in a reaction container (e.g. a photometer), etc. In a multi-sample analysis, each time after the incubation unit transports a target reaction container to a target executing station via a self-adaptive rotation. Only a specific operation can be performed on the target reaction container in the target executing station. Since the other reaction containers may not be located at other executing stations, in which the operations required by the other reaction containers can be performed, the other reaction containers may not be treated in the other executing stations simultaneously with the target reaction container. Therefore, the incubation unit needs to rotate many times, so that a series of operations such as moving a reaction container in, injecting a sample, injecting a reagent, and moving a reaction container out, can be performed successively. For a multi-sample analysis, the inefficiency of this serial fashion test mode adversely limits the test flux of the luminescence immunity analyzer.